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11.
Jiménez Esperanza Piniella Dolores Giménez Cecilio Zafra Francisco 《Neurochemical research》2022,47(1):138-147
Neurochemical Research - The glycine transporter GLYT1 participates in inhibitory and excitatory neurotransmission by controlling the reuptake of this neuroactive substance from synapses. Over the... 相似文献
12.
Ostrosky EA Marcondes EM Nishikawa Sde O Lopes PS Varca GH Pinto Tde J Consiglieri TV Baby AR Velasco MV Kaneko TM 《AAPS PharmSciTech》2011,12(2):732-737
Even though the synthetic preservatives may offer a high antimicrobial efficacy, they are commonly related to adverse reactions
and regarded as having potentially harmful effects caused by chronic consumption. The development of natural preservatives
provides a way of reducing the amount of synthetic preservatives normally used in pharmaceutical and cosmetic preparations.
In addition, these agents have less toxic effects and represent a possible natural and safer alternative of the preservatives.
The purpose of this research was to evaluate the Rubus rosaefolius Smith extract efficiency as a natural preservative in base formulations. Of the extract, 0.2% (w/w) was assayed for its effectiveness of antimicrobial protection in two different base formulations (emulsion and gel). The
microbial challenge test was performed following the standard procedures proposed by The United States Pharmacopoeia 33nd,
European Pharmacopoeia 6th, Japanese Pharmacopoeia 15th, and the Cosmetics, Toiletries, and Fragrance Association using standardized
microorganisms. The results demonstrated that R. rosaefolius extract at the studied concentration reduced the bacterial inocula, satisfying the criterion in all formulations, even though
it was not able to present an effective preservative behavior against fungi. Thus, the investigation of new natural substances
with preservative properties that could be applied in pharmaceutical and cosmetic products is relevant due to the possibility
of substituting or decreasing the concentration of synthetic preservatives, providing a way for the development of safer formulas
for the use of consumers. 相似文献
13.
14.
Rodríguez Patino JM Fernandez MC Rodríguez Niño MR Sanchez CC 《Biomacromolecules》2006,7(9):2661-2670
In this work, we have analyzed the structural, topographical, and surface dilatational characteristics of pure beta-lactoglobulin adsorbed films and the effect of the self-assembly of monoglycerides (monopalmitin or monoolein) in beta-lactoglobulin films at the air-water interface. Measurements were performed in a single device that incorporates a Wilhelmy-type film balance, Brewster angle microscopy, and interfacial dilatational rheology. The structural and topographical characteristics of beta-lactoglobulin adsorbed and spread films are similar. However, the surface dilatational modulus of beta-lactoglobulin films shows a complex behavior depending on film formation. The self-assembly of monoglyceride in a beta-lactoglobulin adsorbed film has an effect on the structural, topographical, and dilatational properties of the mixed films, depending on the interfacial composition and the surface pressure (pi). At low pi, a mixed film of monoglyceride and beta-lactoglobulin may exist. At high pi (after the collapse of beta-lactoglobulin), the mixed films are dominated by monoglyceride molecules. However, the small amounts of collapsed beta-lactoglobulin have a significant effect on the surface dilatational properties of the mixed films. Protein displacement by monoglyceride is higher for monopalmitin than for monoolein. However, some degree of interaction exists between proteins and monoglycerides, and these interactions are more evident in adsorbed films than in spread films. 相似文献
15.
Influence of nutrient management on growth and nutrient use efficiency of two plant species for mineland revegetation
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João M. Carvalho Silvio J. Ramos Antonio E. Furtini Neto Markus Gastauer Cecilio F. Caldeira Jr. José O. Siqueira Maria L. S. Silva 《Restoration Ecology》2018,26(2):303-310
Rehabilitation of degraded areas by mining activities is necessary to achieve sustainable mining. For an effective revegetation, the understanding of plant growth and the nutrient requirements of native plant species, especially those with the potential to be used in the rehabilitation of mined areas such as waste piles or mine pits, is indispensable. In this study, we evaluated the growth performance, nutrient levels, and nutrient use efficiency of an endemic plant (Mimosa acutistipula var. ferrea) and ruderal shrub (Solanum crinitum) that are both found in ferriferous savannas, locally called “canga” in Carajás Mineral Province, Brazil. An experiment was conducted under greenhouse conditions using samples of three different soils (oxisol, canga soil, and iron mining waste) without and with nutrient application; additionally, an omission trial was carried out in canga soils. Fertilization increased the growth of both plant species in all substrates. Macronutrient omission reduced the growth of plants stronger than micronutrient omission, indicating that the lack of N, P, and K may especially impact the rehabilitation of areas. The growth of S. crinitum was higher than M. acutistipula var. ferrea, highlighting its preponderance in mineland rehabilitation, although concerns regarding its role as a ruderal species persist. Therefore, further research is necessary for a risk assessment of the propagation of S. crinitum within mineland restoration projects. 相似文献
16.
Second-site reversion of a human immunodeficiency virus type 1 reverse transcriptase mutant that restores enzyme function and replication capacity.
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17.
Antonio V. Bordería Ramon Lorenzo-Redondo Maria Pernas Concepción Casado Tamara Alvaro Esteban Domingo Cecilio Lopez-Galindez 《PloS one》2010,5(4)
Background
Fitness recovery of HIV-1 “in vitro” was studied using viral clones that had their fitness decreased as a result of plaque-to-plaque passages.Principal Findings
After ten large population passages, the viral populations showed an average increase of fitness, although with wide variations among clones. While 5 clones showed significant fitness increases, 3 clones showed increases that were only marginally significant (p<0.1), and 4 clones did not show any change. Fitness recovery was not accompanied by an increase in p24 production, but was associated with an increase in viral titer. Few mutations (an average of 2 mutations per genome) were detected in the consensus nucleotide sequence of the entire genome in all viral populations. Five of the populations did not fix any mutation, and three of them displayed marginally significant fitness increases, illustrating that fitness recovery can occur without detectable alterations of the consensus genomic sequence. The investigation of other possible viral factors associated with the initial steps of fitness recovery, showed that viral quasispecies heterogeneity increased between the initial clones and the passaged populations. A direct statistical correlation between viral heterogeneity and viral fitness was obtained.Conclusions
Thus, the initial fitness recovery of debilitated HIV-1 clones was mediated by an increase in quasispecies heterogeneity. This observation, together with the invariance of the consensus sequence despite fitness increases demonstrates the relevance of quasispecies heterogeneity in the evolution of HIV-1 in cell culture. 相似文献18.
Penélope Serrano-Ortiz Cecilio Oyonarte Oscar Pérez-Priego Borja R. Reverter Enrique. P. Sánchez-Cañete Ana Were Olga Uclés Laura Morillas Francisco Domingo 《Oecologia》2014,175(3):1005-1017
Climate change may alter ecosystem functioning, as assessed via the net carbon (C) exchange (NEE) with the atmosphere, composed of the biological processes photosynthesis (GPP) and respiration (R eco). In addition, in semi-arid Mediterranean ecosystems, a significant fraction of respired CO2 is stored in the vadose zone and emitted afterwards by subsoil ventilation (VE), contributing also to NEE. Such conditions complicate the prediction of NEE for future change scenarios. To evaluate the possible effects of climate change on annual NEE and its underlying processes (GPP, R eco and VE) we present, over a climate/altitude range, the annual and interannual variability of NEE, GPP, R eco and VE in three Mediterranean sites. We found that annual NEE varied from a net source of around 130 gC m?2 in hot and arid lowlands to a net sink of similar magnitude for alpine meadows (above 2,000 m a.s.l) that are less water stressed. Annual net C fixation increased because of increased GPP during intermittent and several growth periods occurring even during winter, as well as due to decreased VE. In terms of interannual variability, the studied subalpine site behaved as a neutral C sink (from emission of 49 to fixation of 30 gC m?2 year?1), with precipitation as the main factor controlling annual GPP and R eco. Finally, the importance of VE as 0–23 % of annual NEE is highlighted, indicating that this process could shift some Mediterranean ecosystems from annual C sinks to sources. 相似文献
19.
Quintero J López-Muñoz F Alamo C Loro M García-Campos N 《Attention deficit and hyperactivity disorders》2010,2(3):107-113
Up to 30% of patients with attention-deficit hyperactivity disorder (ADHD) treated with psychostimulants discontinue the treatment because of intolerance or lack of therapeutic response. Therapeutic alternatives are needed for such patients. In the present case series, we study the effectiveness of reboxetine over a period of 6 months in a sample of 14 children diagnosed with ADHD according to DSM-IV-TR criteria, who had responded only partially or had presented poor tolerance to conventional treatment with methylphenidate. Clinical efficacy was evaluated through the application of the 18-item Attention-Deficit Hyperactivity Disorder Rating Scale (ADHD-RS-IV) and the Clinical Global Impressions-Global Improvement Scale (CGI-I). Percentages of responders (ADHD-RS ≥ 25%) and improvers (CGI-I absolute value < 4) were 90.9 and 72.7%, respectively. No serious side-effects were observed during treatment, the most frequent effects being headaches and insomnia. The initial findings of our study show that reboxetine may constitute an effective tool for long-term treatment of children with ADHD who present poor response or poor tolerance to initial treatment with methylphenidate. 相似文献
20.
Surface pressure isotherms and structural and surface dilatational properties of three hydroxypropylmethycelluloses (HPMCs, called E4M, E50LV, and F4M) adsorbed films at the air-water interface were determined. In this work we present evidence that HPMC molecules are able to diffuse and saturate the air-water interface at very low concentrations in the bulk phase. As bulk concentration increased, structural changes at a molecular level occurred at the interface. These changes corresponded to transition from an expanded structure (structure I) to a condensed one (structure II). When the surface concentration of HPMC was high enough, the collapse of the monolayer was observed. The three HPMCs formed very elastic films at the air-water interface, even at low surface pressures. E4M showed features that make it unique. For instance it showed the highest surface activity, mainly at low bulk concentrations (<10(-4) wt %). The differences observed in surface activity may be attributed to differences in the hydroxypropyl molar substitution and molecular weight of HPMC. All three HPMCs formed films of similar viscoelasticity and elastic dilatational modulus, which can be accounted for by their similar degree of methyl substitution. 相似文献